Pintle constructions for cutter chains



' April 1957 A. o. BRUESTLE PINTLE CONSTRUCTIONS FOR CUTTER CHAINS Filed April 17, 1953 ATTORNEYS:

PINTLE CONSTRUCTIONS FOR CUTTER CHAINS Application April 17, 1953, Serial No. 349,357

9 Claims. (Cl. 74-451) As is well known, cutting machinery such as is used, for example, in the mining of coal, is provided with power driven cutter chains, certain links of which carry cutting bits in suitable holders. The cutter chains are usually mounted on arms or bars about which they travel; and bits in the various holders are so oriented as to combine in their cutting action to form a cut of suitable width to accept the bar and chain. The links of the chain are pivoted together by pintles. In the normal cutter chain, the link elements which have the cutter bit holders are of double construction having two link cheeks or faces. These link elements are interconnected one to another by means of single link elements. The pintles pass through both cheeks of the double link elements and the cheek of the single link elements which extends between them.

In the development and use of this type of mining machine the tendency is toward more rapid and more powerful operation resulting infaster cutting. The cutter chains are subjected to increasing strains and vibration. Where ditficulties occur through wear or failure, these can normally be traced to the pintles involved.

As set forth in United States Letters Patent 2,280,502, Edwin P. Stenger devised a type of pintle construction having certain operational advantages. It will be understood that the pintles of the cutter chains must not extend beyond the outer faces of the checks of the double link elements, yet they must be securely held against axial displacement and must be relatively easily removed for replacement. Stenger found'that it was advantageous to make his pintles non-rotatable with respect to the double link element so as to localize the rotative wear on the central portion of the pintle itself and onthe bearing surfaces of the single link element. He devisedseveral pintle constructions whereby he could meet these several requirements. His constructions were such that the pintle could be installed by passing it axially through a check of the double link element, next through the cheek of the single link element and finally through the remaining cheek of the double link element. The said remaining cheek was formed with a perforation of non-circular outline, and the pintle on one end at least was shaped to conform to the non-circular outline. In an exemplary form, the pintle, otherwise cylindrical, was made with a flattened portion extending axially, there being also a semi-circular groove in the flattened portion. One of the cheeks of the double link element had pintle-receiving perforations shaped to conform to the partially circular cross-section of the pintle, but flattened to correspond to the fiat on the pintle, and grooved outwardly semi-circularly intermediate the edges of the fiat. This made. it possible to insert a pintle as above described and then pass a rivet through the link elements. This rivet would lie partially in the groove of the pintle, could be passed through the checks of the link elements, either with the pintle or after the pintle was in place, and when headed on both ends (the heads lying in countersinks in the pintle and in the cheeks of the double link element), would hold the pintle against endwise movement. It was not necesnited States Patent 2,788,670 Patented Apr, 16, 1957 sary that either the pintle or the rivet extend beyond the outer side faces of the checks of the double link element.

A primary object of the present invention is the provision of improvements in structures of this class. More specifically, it is an object of the invention to improve and strengthen the pintle while retaining the essential advantages achieved by Stenger.

Another object of this invention is to minimize wear on the pintle and the single link element by substantially increasing the effective bearing surface between the pintle and the single link element. In this connection my object is to accomplish the foregoing while obtaining the assembly advantages achieved by Stenger.

Yet another object of this invention is the obtaining of the foregoing advantages without retooling for the dressing of the non-circular perforations in the cheek or cheeks of the double link element. It will be understood that these non-circular perforations are ordinarily dressed by means of broaches, which are quite expensive.

These and other objects of my invention which will be set forth hereinafter or will be apparnt to one skilled in the art upon reading these specifications, I accomplish by that procedure and in those constructions and arrangements of parts of which I shall now describe certain exemplary embodiments. Reference is made to the accompanying drawings wherein:

Figure 1 is an exploded partial side elevation of cutter chain elements showing the single and double elements and one form of my pintle construction.

Figure 2 is a perspective view showing my pintle with a sleeve in operative relation to it together with a rivet which may be employed in holding the pintle against endwise movement.

Figure 3 is a perspective view showing the pintle and sleeve in disassembled relationship.

Figure 4 is a partial sectional view taken along the line 4-4 of Figure 1.

Figure 5 is a partial sectional view taken along the line S-5 of Figure 4.

Figure 6 is a partial sectional view, corresponding to Figure 4 in position, but showing another type of pintle construction.

Figure 7 is a partial sectional view taken along theline 77 of Figure 6.

Figure 8 is a perspective view showing the type of pintle and rivet employed in the structures of Figures 6 and 7, these elements being in disassembled relationship.

Figure 9 is a partial sectional view corresponding in position to Figure 4, but involving another type of pintle and rivet construction.

Figure 10 is a partial sectional view taken along the line Ill-i Figure 9.

Figure 11 is a perspective view showing the pintle and rivet used in the constructions of Figures 9 and 10, these elements being in disassembled relationship.

Figures 12 and 13 are each partial sectional views corresponding in position to Figure 10, and showing different ways in which sleeves may be used with the pintle of Figure 11.

Referring first to. Figure l, I have there illustrated a portion of a cutting chain comprising double link ele ments 11 and single link elements 12. Although not illustrated in this. figure, it. will be understood that each double link element has a check 13 and an opposite cheek 14 (see Figures 4 and 6). The two cheeks 13 and 14 are held together and in spaced relationship by a construction 15 at the outer side of the link element, this construction forming a socket to receive a bit, or a combination of bit and bit holder. Normally, thetwo cheeks 13 and 14, and the socket portion 15, are integral parts of a single forging or casting. The precise nature of the socket element and. the bit holder or bit construction does not form a limitation on this invention. Hence, they will not be described herein. 7

The checks 13 and 14 of the double link element are spaced from each other sufliciently to accept between them the ends or checks of the single link elements 12, as will be understood from Figures 1, 4 and 6. It will be clear that when these parts are in assembled relationship, the pintles 16 will have to be installed by passing them endwise through the perforations in the cheeks 13, 12 and 14. Moreover, if the pintles are to be non-rotatable with respect to the double link element, one at least of the cheeks of the double link element must be provided with a perforation which is non-circular, and the pintle must have at least at one end a correspondingly noncircular cross-section.

In Figure 3 I have illustrated at 16 a pintle of a type shown in the said Patent 2,280,502. It will be observed that this pintle is generally cylindrical, but that it has been flattened as at 17 on one side throughout its length, that it is grooved longitudinally in the flattened portion as at 18, and that it has countersink-s or recesses at the ends of the grooved portion as at 19. In order to increase the effective bearing surface of the pintle in the cheek 12 of the single link element, I make use of a sleeve member shown in Figure 3. This sleeve member 20 has an outer cylindrical surface 21 and is perforated longitudinally, being characterized within the perforation by a partial cylindrical surface 22, a flat indicated at 23, and an outwardly extending semi-circular groove 24 which will match the groove 18 in the pintle.

If the sleeve 20 be placed over the pintle 16 as shown in Figure 2, it will now be clear that the shank of a rivet 25 may be passed through the cooperating grooves 24 and 18, and that the head 25a of the rivet can lie in the countersink 19. The sleeve 20 is prevented from rotating with respect to the pintle, by reason of the shank 25 of the rivet and through the coaction of the flats 17 and 23. This means that the effective bearing surface between the pintle 16 and the cheek of the link 12 is no longer circumscribed by the engagement of the actual pintle surface with the inner surface of a perforation or bushing in the intermediate link 12, but rather has become a very much larger surface engagement involving the outer cylindrical surface of the sleeve 20 and the inner surface of a larger perforation or bushing in the check of the intermediate link.

In assembling the structure thus far described, the sleeve element 20 can be inserted in the check of the intermediate link 12 and the cheek placed between the cooperating cheeks at one end of the double link element 11. Thereupon the pintle may be passed endwise through the cheeks of the double link element and the sleeve, it being only necessary to align the openings of these elements. The rivet 25 may then be passed through the structure as will be clear from the various figures until the rivet head 25a lies in the pintle recess 19 and the corresponding recess 1% in the cheek of the double link element (see Figure 1). Heading the rivet in the usual fashion will result in a second head 25b lying in corresponding recesses at the opposite check of the double link element, and the pintle will be held firmly against endwise movement. This is illustrated in Figure 4, where a bushing in the cheek of the intermediate link element 12 is marked 26.

Further, it will now be clear that in this exemplary construction the perforation in the sleeve 20 has the same shape as the corresponding perforation in one or both cheeks (13 or 14) of the double link element 11. The same broaches which are employed to dress the openings in the cheeks 13 or 14 may be used to dress the opening in the sleeve 20, so that retooling is not necessary.

The wear resisting ability of the pintle construction of the Stenger patent referred to above is very greatly increased by that increase in the bearing area which results from the use of the sleeve 20 as described, while the other advantages of the Stenger pintle construction are retained.

Because of the increased demands for high speed and heavy duty operation in cutter chains of the type under discussion, the matter of pintle strength and ability to withstand shock becomes of importance. It has been found (see Figure 3) that the strength and shock resistance of a pintle is somewhat diminished not only by the formation of the flat 17 but also by the formation of the groove 18 therein. In Figure 8 I have illustrated a type of pintle at 27 which is provided with a flat 28, but is not characterized by a groove. In using this type of pintle, the rivet 29 (see the same figure) will have a portion of its shank milled or otherwise cut away as at 30 to correspond to the fiat 28. Hence, this portion of the rivet shank will be semi-circular in cross-section.

The pintle 27 is provided at its ends with recesses 31 and 32. One of these will accept the preformed head 29a of the rivet, while the other will accept the head 2% which will be formed on the rivet after the pintle is in place. In Figure 8 I have shown the recesses 31 and 32 terminating at the bottom in smaller recesses 31a and 32a. This makes it unnecessary to mill the fiat 30 on the rivet shank right up to the preformed head 29a.

When the pintle of Figure 8 is to be installed, the rivet 29 is assembled to it first, whereupon the pintle and rivet may be installed as set forth above, excepting that the pintle and rivet combination must be started through the aligned cheeks of the links from that end on which the rivet is not headed.

When the pintle and rivet combination is in final place, the protruding shank of the rivet may then be hammered or compressed to form the head 2%, and the pintle will be held against axial movement.

The pintle and rivet combination of Figure 8 may be employed in a cutter chain with or without the sleeve 20, as will now be evident. Where a sleeve is employed, as in Figures 6 and 7, the sleeve will be held against rotation with respect to the pintle 27, both by reason of the fiat 28 and by reason of the shank of the rivet 29. While the rivet as an individual structure is weakened by the m-illingaway f a portion of its shank as at 30, this is not of consequence because there are no large forces tending to move the pintle endwise in the operating chain, and the remaining portion of the rivet shank is amply able to withstand the axial forces which exist.

In Figure 11 I have shown another form of pintle having enhanced strength characteristics. This pintle 33 is devoid of any longitudinal flat. It is, however, characterized by a semi-circular, longitudinal groove 34 terminating at each end in rivet head recesses 35 and 36.

This type of pintle may be used in various ways. One mode of use is in connection with a rivet 37 also illustrated in Figure 11. Thisrivet preferably has a preformed head 37:: at one end. The shank of the rivet intermediate its ends is milled or cut away to form a surface 38 which is not a flat but rather a continuation of the cylindrical surfaces of the pintle 33. When using this form of construction the rivet is first passed through the perforations in the cheeks of the links and positioned with its head 37a lying in a recess 19a of one of the cheeks of the double link element 11. Then the pintle 33 may he slid into position through the perforations in the cheeks in the opposite direction. The rivet is next treated to form the head 37b on its opposite end. In this construction the pintle is held against rotation with respect to the cheeks 13 and 14 of the double link element 11 primarily by the engagement of the rivet heads in the recesses 19min the cheeks of that link element. Ordinarily, this is sufiicient; but it does not constitute a departure from the teachings of this invention to form one end of the pintle to a non-circular cross-sectional shape and to provide an opening or perforation of corresponding shape in a cheek of the double link element. Thus, one of the cheeks of the double link element may be provided with openings such as are illustrated in Figure 1, while the opposite check of the same element and the cheek of the single link element may be provided with circular openings. A flat maybe milled at one end of the pintle only.

The construction thus far described in connection with Figure 11 is especially valuabie for use without a sleeve, as illustrated in Figures 9and 10; because the pintle itself is of an enhanced strength and the combination of pintle and rivetpresents circumferentially a continuous bearing surface as Will be evident.

It is possible to employ a sleeve in connection with the pintle 33 of Figure 11, and still arrange to have the sleeve held against rotation with respect to the pintle. One Way of doingthis is illustrated in Figure 12. Here a sleeve 39 is providedhavinga longitudinal perforation which is circular in cross-section excepting that it is grooved as at 40 with a semi-circular groove to match the groove 34 in the pintle. A rivet having a full round shank (i. e. not cut away as at 38) is used. The assembly of the structure will be clear from the figure. The rivet shank prevents the rotation of the sleeve 39 with respect to the pintle 33.

Yet another modification is illustrated in Figure 13. A pintle 41 is formed having either a full cylindrical crosssectional shape intermediate its ends or else provided with a fiat of minor extent as at 42. At the ends of the pintle there will be the rivet head recesses previously described. The pintle is employed with a rivet, the shank portion of which is cut away intermediate its ends so as to provide a surface which either corresponds to the flat 42 or to the cylindrical surface of the pintle as the case may be. This pintle and rivet construction may be employed with the same sleeve 39 as has been described in connection with Figure 12. Again it Will be the shank of the rivet 43 which prevents the rotation of the sleeve with respect to the pintle, the rivet in turn being held against movement with respect to the pintle primarily by reason of the heads at the ends of the rivet. In the structure illustrated in Figure 13, the rivet will be assembled to the pintle before the combination is passed endwise through the perforations in the link elements of the cutter chain.

Modification may be made in the structures herein disclosed Without departing from the spirit of the invention. By way of a single non-limiting example, it may be pointed out that Whereas I have disclosed certain structures in which rivet elements are cut away intermediate their ends, but throughout the entire length of the rivet which passes through the cheek of the single link element and beyond, it is readily possible to cut away the rivet shank for a lesser longitudinal distance and to shape the contiguous portions of the pintle and/or the sleeve accordingly.

Having this described by invention in certain exemplary embodiments, What I claim as new and desire to secure by Letters Patent is:

1. In a cutter chain or like structure having cooperating perforated link elements adapted to be pivoted together by a pintle, a pintle of generally cylindrical crosssection but having a longitudinal flat, recesses at the ends of said pintle to accept the heads of a rivet, a rivet having a shank of generally cylindrical cross-section, the intermediate portion of said shank being of reduced noncircular cross-section to form a flat adapted to seat against said first named fiat, one of said cooperating link elements having a cylindrical perforation therein and another of said cooperating link elements having therein a perforation and a recess to accept the head of said rivet.

2. The structure claimed in claim 1 wherein said last mentioned link element has a perforation which responds to the flat of said pintle and is grooved to accept the shank of said rivet.

3. In a cutter chain or like structure having cooperating perforated link elements adapted to be pivoted together by means of a pintle, a pintle of generally cylindrical crosssection but having a longitudinal flat and a semi-circular groove extending longitudinally of the flat, a sleeve having a perforation to accept saidupintle, having acorrespond' ing flat andan outwardly extending groove coacting; with the first mentioned groove, the perforation in one of" said link elements shaped to accept said sleeve, the outer surface of said sleeve and the inner surface of said perforation both being cylindrical, another of said link elements having a perforation shaped similarly to the perforation in said sleeve, and a headed rivet extending longitudinally of the sleeve and pintle with its shank passing through the grooves therein and acting to hold said several: elements in assembly.

4. The structure claimed in claim 3 wherein said rivet is headed at both ends and wherein the heads of said rivet lie in recesses in the ends of said pintle and in a link ele ment in which the ends of said pintle engage.

5. In combination in a cutter chain or like structure, link elements havingperforated cheeks adaptedto be-assembled with their perforations in alignment, a solid pintle extending through the said perforations and adapted to pivot said link elements one to the other, a sleeve element surrounding that portion of the pintle which passes through one of said link elements, said pintle and said sleeve having cooperating flats acting to prevent relative rotation, a rivet having a shank portion, cooperating longitudinally extending grooves both in said sleeve and in said pintle engaged by the shank portion of said rivet, said rivet acting to prevent the endwise movement of said pintle and said shank portion thereof acting to prevent rotation of said pintle with respect to said sleeve element, and means to prevent rotation of said pintle with respect to the other of said link elements.

6. In a cutter chain or like structure having perforated link elements adapted to be pivoted together by means of a pintle, a solid pintle of constant cross-sectional area throughout the middle portion of its length but having a flat, a sleeve of a length to extend through one of the link elements, said sleeve element being perforated to accept said pintle, said perforation having a cooperating flat, another link element having a perforation including a flat cooperating with the flat on said pintle, a longitudinally extending groove in said sleeve in the area of said fiat, recesses in the ends of said pintle, and a headed rivet extending longitudinally through said perforations and seated in said groove and said recesses, said rivet acting to hold said elements in assembly.

7. In a cutter chain or like structure having link elements with perforated cheeks adapted to be pivoted together by means of a pintle, a solid pintle having a noncircular cross-sectional area constant throughout the middle portion of its length, a sleeve having a perforation to accept said pintle, said perforation also having a non-circular cross-section whereby said sleeve is prevented from rotating with respect to said pintle, said sleeve having externally a cylindrical shape, one of said perforated link elements having a perforation of a size and cylindrical shape to accept said sleeve and another of said perforated link elements having a non-circular perforation of a size and shape to accept an end of said pintle extending beyond said sleeve whereby said pintle is prevented from r0- tating with respect to said link element, a longitudinally extending groove in said sleeve and a recess in said pintle, and a headed rivet extending through said perforations and seated in said groove and said recess, said rivet acting to hold said elements in assembly.

8. In a cutter chain or like structure having co-operating perforated link elements adapted to be pivoted together by a pintle, a pintle of generally cylindrical crosssection but having a longitudinal flat, recesses at the ends of said pintle to accept the heads of a rivet, a rivet having a shank, said shank being cut away intermediate its ends to correspond to said flat, one of said cooperating link elements having a cylindrical perforation therein and another of said cooperating link elements having therein a perforation and a recess to accept said rivet, said last named perforation responding to the flat of said pin- 7 tle and grooved to accept the shank of said rivet, in combination with a sleeve perforated to accept said pintle and rivet and provided with a fiat portion contacting the flat on said pintle, whereby said sleeve is non-rotatably mounted with respect to said pintle.

9. In a cutter chain or like structure having cooperating link elements adapted to be pivoted together by a pintle, a pintle of cylindrical cross-section but having a longitudinal semi-circular groove to accept the shank of a rivet, recesses at ends of said longitudinal groove to accept the heads of the rivet, and a rivet having a shank of generally cylindrical cross-section, the intermediate portion of said shank being of reduced cross-section to form a surface which is a continuation of the cylindrical surface of said pintle when said rivet is seated in said longitudinal groove, one of said cooperating link elements having a cylindrical perforation therein and another of said References Cited in the file of this patent UNITED STATES PATENTS 627,694 Howe June 27, 1899 996,726 Yeager Aug. 9, 1910 2,012,947 Bosnian Sept. 3, 1935 2,068,666 Dunlop Jan. 26, 1937 2,280,502 Stenger Apr. 21, 1942 2,310,016 Doberstein Feb. 2, 1943 2,347,329 Morrow Apr. 25, 1944 2,398,107 Morrow Apr. 9, 1946 2,399,166 Cartlidge Apr. 30, 1946 2,623,398 Barrett Dec. 30, 1952 

